Apparatus for making electrical connections



n 1965 J. R. VICKERY, JR 3,186,075

AR US FOR MA V KING ELECTRICAL CONNECTIONS Filed April 15, 1964 3 Sheets-Sheet l June 1, 1965 J. R. VICKERY, JR 3,186,075

APPARATUS FOR MAKING ELECTRICAL CONNECTIONS Filed April 13, 1964 s Sheets-Sheet 2 APPARATUS FOR MAKING ELECTRICAL CONNECTIONS Filed April 15, 1964 June I, 1965 J. R. VICKERY, JR

3 Sheets-Sheet 5 United States Patent 3,186,075 APPARATUS FOR MAKING ELECTRICAL C(INNECTIONS John Roy Vickery, Jr., York, Pa., assignor to AMP Incorporated, Harrisburg, Pa. Filed Apr. 13, 1964, Ser. No. 359,143 4 Claims. (Cl. 29-203) This invention relates to apparatus for making an electrical connection between a terminal post'and a conductor by means of an open-sided clip which is adapted to embrace the post and to hold the conductor against the surface of the post.

The copending application of Robert F. Cobaugh, Serial No. 171,074, filed February 5, 1962, discloses and claims methods and apparatus for making electrical connections between terminal posts and conductors by means of clips which are movable over a mandrel, past a transversely extending conductor, and onto the terminal post in a manner such that the conductor is dragged over the mandrel and onto the post. One type of apparatus for forming electrical connections by means of such clips is disclosed in the above-identified Cobaugh application to comprise a pneumatically actuated hand tool having a reciprocable clip pusher by means of which the clip is moved over the mandrel and onto the post. Several alternative and improved types of pneumatically actuated hand tools are disclosed in application Serial No. 250,300 and application Serial No. 302,896.

Most of the previously known hand tools for forming clip-type electrical connections have been provided with a piston-cylinder for driving the terminal clip over the mandrel and onto the post in one uninterrupted stroke of the clip pushing means. The procedure for forming an electrical connection with these prior art tools is to insert the end of the wire into an opening in the mandrel, position the tool against, and in alignment with, the terminal post, and actuate the clip pushing means to drive the clip past the wire, over the mandrel and onto the post.

It has been discovered that it is advantageous to interrupt the stroke of the clip pushing means in a manner such that during a first portion of the stroke of the pushing means, the clip is driven over the mandrel and past the conductor until the clip projects slightly beyond the end of the mandrel. During the second portion of the interrupted stroke, the clip is driven a further distance past the end of the mandrel and onto the terminal post. One advantage of this alternative procedure is that the technician using the tool can hold it in any convenient manner (rather than against the post) while he is carrying out the initial steps of inserting the wire into the mandrel and effecting the first portion of the stroke of the clip pushing means. The technician can thereafter position the tool in alignment with the terminal post and actuate the clip pushing means for the second portion of its stroke to drive the clip onto the post and form the electrical connection. This split cycle or interrupted stroke technique is described fully in the copending application of Robert F. Cobaugh, et al., Serial No. 341,311, filed January 30, 1964. The copending Cobaugh et al. application also discloses a manually actuated hand tool having the interrupted stroke feature necessary for this interrupted stroke technique of making clip type electrical connections.

The present invention relates to interrupted stroke type tools having power actuated means, such as a pneumatic piston-cylinder, for driving the reciprocable member through its stroke in accordance with the teachings of the above-identified Cobaugh, et al. application.

It is accordingly an object of the present invention to provide an improved tool for forming electrical connections between terminal posts and conductors by means of 3,186,075 Patented June 1, 1965 ice terminal clips. A further object is to provide power actuated hand tool having means for interrupting the stroke of the reciprocable member of the tool.

These and other objects of the invention are achieved in a preferred embodiment thereof comprising a pistol gllp type hand tool having a reciprocable clip pusher and a mandrel, the clip pusher being driven along a rectilinear path by means of a pneumatic piston-cylinder. The forward stroke of the clip pusher is interrupted by means of a stop which normally is disposed on the path of the clip pusher so that the clip is pushed through only a portion of its total travel until the clip pusher moves against the stop member. This stop member is automatically moved away from the path of reciprocation of the clip pusher upon a slight rearward movement of the pusher after the first portion of the forward stroke has been completed. After movement of the stop member out of engagement with the clip pusher, the clip pusher is permitted to complete its forward stroke to drive the terminal clip past the mandrel and onto a terminal post.

In the drawing:

FIGURE 1 is a perspective exploded view of a preferred form of pneumatically actuated hand tool in accordance with the invention;

FIGURE 2 is a side view of the stroke interrupting mechanism of the tool of FIGURE 1 showing the parts in the positions they occupy when the piston rod is in its retracted position prior to the initiation of an operating cycle of the tool;

FIGURES 3, 4 and 5 are views similar to FIGURE 2 but showing the positions of the parts at various stages of the operating cycle of the tool;

FIGURE 6 is a view taken along the lines 6-6 of FIGURE 2;

FIGURE 7 is a perspective view of a terminal clip for forming an electrical connection between a conductor and a terminal post, this clip being of the type adapted to be applied to the terminal post by the tool of FIGURE 1;

FIGURE 8 is a perspective view showing an electrical connection between a conductor and a terminal post formed by the terminal clip of FIGURE 7;

FIGURE 9 is a fragmentary side view showing the relative positions of the terminal clip, the mandrel, and the clip pusher of the tool of FIGURE 1 at the time of interruption of the forward stroke of the clip pusher;

FIGURE 10 is a view showing the relative positions of the clip pusher, the man-drel, and the terminal clip at the conclusion of the forward stroke of the clip pusher.

Referring first to FIGURES 7 and 8, a typical terminal clip of the type described fully in the above-identified Cobaugh application, Serial No. 171,074, is of generally channel-shaped cross-section having a web 4 from which sidewalls 6 extend, these sidewalls being reversely curled as shown at 8 towards each other and towards the web. Ears 10 are struck up from the web at the leading end thereof to function as an insulation support for a wire 14 when the clip is applied to a terminal post 12 as shown in FIGURE 8. In the completed electrical connection, the conducting core of the wire extends upwardly, as viewed in FIGURE 8, between the underside of the web 4 and the surface of the post 12 and the clip embraces the terminal post in a manner such that the conducting core of the wire is pressed firmly against the surface of the post to establish an electrical connection.

FIGURE 1 shows the general features of a commonly known type of pneumatically actuated hand tool incorporating a stroke interrupting mechanism in accordance with the principles of the instant invention. Since most of the structural features of the tool of FIGURE 1 are known to the art, excepting those structural features which relate to'my improved stroke interrupting mechanism, only a brief description will be supplied of the general features of the tool with reference being made, where appropriate, to copending applications which describe these structural features in more detail.

The tool 14 of FIGURE 1 is of a pistol grip type comprising a handle 16 having a double acting pneumatic piston-cylinder 18 mounted on its upper end. The handle 16 contains a suitable valve mechanism (not specifically shown) which controls the admission of compressed air through an air hose 19 to the cylinder 18 in a manner such that air is admitted to this cylinder at its forward end when the trigger 20 is not pressed so that the piston rod is normally biased rearwardly in the cylinder. When the trigger 20 is pressed, the compressed air is exhausted from the forward end of the cylinder and is admitted to the rearward end thereof through a suitable air line 21 to drive the piston rod rightwardly in FIGURE 1. The piston rod (FIGURE 6) extends through the forward cylinder head 29 and has an L-shaped block 28 secured to its end.

The tool mechanism is contained between a pair of housing plates 22, 24, the plate 22 having a flange 23 on its upper side which projects across the upper side of the tool towards the housing plate 24. The two housing plates are secured together by means of fasteners indicated at 26. The block 28 on the end of the piston rod is coupled to a clip pusher 32 by means of a suitable overload release mechanism 30 which functions to limit the stress imposed on the terminal clip when it is applied to a post as described fully in the copending application of Robert F. Cobaugh, Serial No. 302,896, filed August 19, 1963. The clip pusher 32 is reciprocable along a rectilinear path extending over a mandrel generally indicated at 34 which is contained between the frame plates 22, 24. A strip of terminal clips is fed from a suitable reel mounted on a reel bracket 39 through a passageway 40 in a block contained between the housing plates and along a strip feed path extending beneath the clip pusher 32. At the end of this path, the leading clip of the strip is transferred laterally into alignment with the path of movement of the clip pusher by means of a transfer slide 42 which is reciprocated by means of a rocking lever 44 pivotally mounted on the housing plate 22.

More specific details of the structure of the clip feed mechanism, the mandrel, and the clip pusher are disclosed in the previously identified copending applications, Serial No. 302,896 and Serial No. 250,300.

In accordance with conventional practice in the usage of tools of the type shown in FIGURE 1, the end portion of a wire is inserted through a wire guide member 36 disposed above the mandrel 34 and into an opening in the mandrel 34 so that the axis of the wire extends transversely of the path of movement of the clip pusher. Thereafter, in accordance with prior art practice, the piston-cylinder 18 is actuated to drive the clip pusher through its forward stroke and to push the clip over the mandrel, past the wire, and onto a terminal post to form the electrical connection shown in FIGURE 8.

With most of the prior art tools, it was necessary for the operator to insert the wire into the opening of the mandrel, position the tool against the post and then squeeze the trigger 20 to carry out the operating cycle of the tool. This prior art technique was sometimes found to yield less than optimum results, particularly where the operator was relatively unskilled and prone to carelessness. The above-identified Cobaugh et al. application, Serial No. 341,311, discloses a manually actuated tool in which the stroke of the clip pusher is divided into two portions for the purpose of rendering the technique of using the tool more susceptible to control by unskilled or careless technicians. In accordance with the teachings of the Cobaugh, et al. application, the clip pusher is first caused to travel through a major portion of its stroke during which it pushes the clip over the mandrel, past the wire, and up to and slightly beyond the end of the mandrel. FIGURE 9 shows the position of the end of the clip pusher and the terminal clip at the conclusion of the first portion of the stroke of the clip pusher in accordance with the teachings of the Cobaugh et al. application, Serial No. 341,311. During the second portion of the interrupted stroke, the clip is, of course, pushed further beyond the end of the mandrel and onto the terminal post 12 to complete the electrical connection as shown in FIG- URE 10. The advantage of this technique is that the operator can insert the wire into the opening in the mandrel and actuate the clip pusher to cause it to travel through the first portion of its stroke (that is, until the parts assume the positions of FIGURE 9) while he is holding the tool in a convenient manner. Thereafter, the operator need only position the end of the mandrel in alignment with the post and actuate the clip pusher to cause it to travel through the remaining portion of its stroke. The portion of the clip which projects beyond the mandrel functions as a guide means for the terminal post to assure substantially perfect alignment of the mandrel with the post during the second portion of the stroke of the clip pusher. The present invention relates to a specific form of mechanism for controlling the action of the piston cylinder 18 and the clip pusher 32 in a manner such that the interrupted stroke technique of the aboveidentified Cobaugh, et al. invention is achieved.

Referring now to FIGURES 2-6, the stroke interrupting mechanism comprises a pin 46 on one side of the block 25. Pin 46 has an enlarged cylindrical head 48 which bears slidably against the internal surface of a plate 23a so that when the clip pusher moves forwardly from the position shown in FIGURE 1 of the drawing, the pin moves along a rectilinear path over the surface of the plate 23a from the position shown in FIGURE 2 to the position shown in FIGURE 5. The plate 23a is secured to, and disposed against, the plate 22 as shown in FIGURE 6. The pin 46 bears against the upper edge 60 of a lever 50 which is pivotally mounted intermediate its ends on a pivot pin 54. Pin 54 has a roller 56 integral therewith which is disposed in a relatively short slot 58 in the housing plate 23a. Bars 61, 63 are provided on the upper side of the lever 50 at each end thereof and the opposed edges of these ears are inwardly curved to form opposed pockets 62, 64 having radii conforming to the radius of the head 48 of the pin 46. The ear 63 on the right-hand side of the lever 50, as viewed in FIGURE 2, has a sloping leading edge 65 which cooperates with a complementary edge 82 on a lever arm 72 as described below. A stiff wire spring 66 bears against the lower edge of the lever 50, extends leftwardly as viewed in FIGURE 2 beneath this edge, and is secured as shown at 68 to the plate 23a. A stop pin 70 is mounted in the housing plate 23a adjacent to the right-hand side of the lever 50 and prevents the lever from swinging in a clockwise direction about its pivotal axis 54 when the parts are in the positions shown in FIGURE 2. A notch 62 is provided on the lower side of the lever 50 to permit limited swinging movement of this lever when it is moved from the position of FIGURE 2 to the position of FIGURE 4 as is described in further detail below.

It will be apparent that when the parts are in the positions shown in FIGURE 2, the spring will bear against the lower edge of the lever 50 on the right-hand side of the pivotal axis 54 so that the lever 50 is biased in a counterclockwise direction although it is prevented from movement in a counterclockwise direction by virtue of the fact that the spring 66 extends past the pivotal axis 50 of the pin 54 and by virtue of the presence of the pin 48 in the pocket 62.

Lever 50 cooperates with a generally L-shaped upper lever 52 pivoted at its apex 76. A long arm 72 of lever 52 extends forwardly towards the nose of the tool and a relatively short depending arm 74 extends downwardly behind the lever 50 when the latter lever is in its retracted position. A pin 78 is provided in the lever 72 intermediate its ends and a roller mounted on this pin is disposed in an arcuate slot 88 in the housing plate 230, the arrangement being such that the lever 72 is permitted to swing along an arc of limited extent about its pivotal axis 76. Forwardly of the pin 78, the lever 72 has a downwardly and forwardly sloping surface 82 on its underside which is complementary to the previously described sloping surface 65 of the lever 50. At its extreme end, the lever 72 is provided with an obliquely and downwardly extending extension 85, the left-hand edge 86 of which functions as a cam surface and which merges with a notch 84.

An overcenter spring mechanism is provided to maintain the lever 72 in either the position shown in FIGURE 2 or the position shown in FIGURE 5, this spring mechanism in the disclosed embodiment comprising a simple wire spring having a sinuous bend secured at one end to the end of the lever and secured at its opposite end to a screw 90 in the plate 230. a

In use, the parts will be in the position shown in FIG- URE 2 at the beginning of the operating cycle. As noted above, compressed air is normally admitted to the forward end of the piston cylinder to maintain the piston rod and the pin 48 in their retracted positions. The operator first inserts the end portion of a wire through the wire guide 36 into the previously described opening in the mandrel and, while holding the tool in any convenient manner, squeezes the trigger 20. Upon squeezing the trigger, the valve mechanism is shifted to exhaust air from the forward end of the cylinder 18 and to admit air to the rearward end thereof causing the piston rod and the pin 48 to move rightwardly from the position of FIGURE 2 to the position of FIGURE 3. During this portion of the cycle, the pin 48 first moves into the arcuate pocket 64 in the car 63 of the lever 50 and drags this lever rightwardly, within the limits permitted by the slot 58, until the roller is disposed against the right-hand side of slot 58. As the lever 50 is moved rightwardly by the pin 48, the edge 65 of the lever moves against the complementary edge 82 on the underside of the lever 52 and causes lever 52 to swing upwardly through a relatively short arc. This arcuate movement of lever 52 permits the right-hand end of the lever 50 to move past the edge 82 and against the lower edge 86 of the lever 52. It should be understood that this limited arcuate movement of the lever 52 is not sufficient to cause the spring 88 to pass over center; that is, the lever is not urged up to the top portion of the slot 80 so that after the ear 63 of lever 58 passes the surface 82 of lever 72, the lever 52 returns to its initial position under the influence of the spring 88.

The forward movement of the pin 48 and the piston rod is effectively stopped when the parts reach the position of FIGURE 3 since the pin 48 is disposed in the pocket 64 of the lever 50 and the roller 56 is disposed against the right-hand side of the slot 58. The operator then releases pressure on the trigger 20 at which time the pin 48 will move rearwardly a very short distance since the compressed air supply will be shifted from the rearward to the forward end of the piston cylinder 18. Upon such limited rearward movement of the pin 46, the spring 66 will cause the lever 50 to swing through a short are in a clockwise direction until the notch 62 moves against the stop pin 70 as shown in FIGURE 4. While the pin 48 will be biased leftwardly when the parts are in the position of FIGURE 4, it will not move leftwardly beyond the position of FIGURE 4 for the reason that it is stopped by the edge portion 83 of the notch 84. The operator can then, in a careful and controlled manner position the mandrel in alignment with, and against the end of, the terminal post 12. After doing so, the operator again squeezes the trigger 20 causing the compressed air supply to be shifted from the forward to the rearward end of the piston cylinder 18 thus causing the piston rod and the pin 46 to move rightwardly from the position of FIG- URE 4 to the position of FIGURE 5. During such movement of the piston rod, the clip is driven from the end 6 of the mandrel and onto the terminal post as shown in FIGURE 10.

During the second portion of the interrupted stroke of the clip pusher, the pin 48 moves against the sloping surface 86 on the lower edge of the lever 52 and swings the lever 52 through a substantial are about its pivotal axis 76 which is sufficient to deform the spring 88 by an amount sufiicient to cause it to shift the lever to the limit of its upward travel as shown in FIGURE 5. When the tool is subsequently removed from the post the trigger 20 is released and the shifting of the compressed air supply to the forward end of the piston-cylinder causes the clip pusher and the pin 48 to move leftwardly from the position of FIGURE 5 to the position of FIGURE 2. During such movement of the pin 48, it engages the upper surface 60 of the lever 50, rides over this surface until it moves into the pocket 62, and thereafter drags the lever 50 leftwardly until the roller 56 is disposed in the left-hand side of the slot 58. Additionally, during such leftward movement of the lever 50, the edge 92 of the lever moves against the depending arm '74 of the lever 52 and swings this lever in a clockwise direction until the spring 88 is again overcentered and the lever is biased downwardly to the position of FIGURE 2. The tool is then ready for the next operating cycle.

It will be apparent from the foregoing description that the pocket 64 of the lever 50 functions as a positive stop which stops the forward motion of the piston rod and, therefore, the clip pusher when the head 48 of pin 46 moves against the edge of the pocket 64. It will also be apparent that the spring 66 functions as a means for disengaging the stop from the clip pusher in that upon leftward movement of the pin 46 from the position of FIGURE 3 to the position of FIGURE 4, this spring causes the lever 50 to move through a slight clockwise are about its pivotal axis 54. Such arcuate movement of the lever 50 has the effect of lowering the pocket 64 of the lever so that the pin 46 and, therefore, the piston rod and the clip pusher can move rightwardly from the position of FIGURE 4 to the position shown in FIG- URE 5.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective against the prior art.

I claim:

1. A tool for pushing a terminal clip onto a terminal post to form an electrical connection between said post and an electrical conductor, said tool comprising, a mandrel conforming to the internal cross-section of said terminal clip, a clip pusher, power means having a stroke of predetermined amplitude for moving said clip pusher along a path extending over, and beyond the end of, said mandrel, stop means for stopping movement of said clip pusher at an intermediate stage of its forward stroke and after said clip has been pushed to the end of said mandrel, and means for disengaging said stop means from said clip pusher thereby to permit completion of the stroke of said clip pusher whereby, the initial portion of the stroke of said clip pusher can be effected while said tool is held in a convenient manner, and the final portion of the stroke of said clip pusher during which said clip is pushed onto said post is carried out as a separate operation.

2. A tool as set forth in claim 1 wherein said stop means comprises a lever pivotally mounted on said tool, said clip pusher being engageable with said lever at said intermediate stage of its stroke, said means for disengagingsaid stop means comprising means for swinging said lever out of engagement with said clip pusher.

3. A tool as set forth in claim 1 wherein said stop means comprises a pair of cooperating levers, said clip' pusher being engageable with a first one of said levers at said intermediate stage of its stroke whereby said clip pusher is stopped at said intermediate stage, said second lever being engageable with said clip pusher upon limited rearward movement of said clip pusher after said forward stroke has been stopped, and means for moving said first lever away from said path after rearward movement of said lever whereby said clip pusher is permitted to complete said forward stroke.

4. A tool of the type intended for making an electrical connection between a terminal post and a conductor by means of a terminal clip adapted to embrace said post, said tool comprising, a mandrel conforming to the internal cross-section of said clip, a clip pusher movable during a forward stroke along a path extending over, and beyond the end of, said mandrel, thereby to push said terminal clip past a transversely extending conductor, over said mandrel, and onto said post, a pneumatic piston-cylinder for actuating said clip pusher, stop means for stopping movement of said clip pusher after a first portion of said forward stroke and after said clip has been pushed partially beyond the end of said mandrel, means for disengaging said first stop means from said clip pusher upon limited rearward movement of said clip pusher, means for moving said clip pusher rearwardly a limited distance after engagement with said stop whereby, after said first portion of said stroke, said tool can be positioned in alignment with said post with said projecting portion of said clip functioning as an aligning means for said tool to align said post with said mandrel, and said clip pusher can thereafter be moved through the remaining portion of said stroke to move said clip onto said post.

References Cited by theExaminer UNITED STATES PATENTS 2,397,872 4/46 Kovacs 7846 2,780,794 2/57 Cresson 339-276 2,885,764 5/59 Shulters et a1. 29203 3,074,155 1/63 Cootes et al. 29206 WHITMORE A. WILTZ, Primary Examiner.

THOMAS H. EAGER, Examiner. 

1. A TOOL FOR PUSHING A TERMINAL CLIP ONTO A TERMINAL POST TO FORM AN ELECTRICAL CONNECTION BETWEEN SAID POST AND AN ELECTRICAL CONDUCTOR, SAID TOOL COMPRISING, A MANDREL COMFORMING TO THE INTERNAL CROSS-SECTION OF SAID TERMINAL CLIP, A CLIP PUSHER, POWER MEANS HAVING A STROKE OF PREDETERMINED AMPLITUDE FOR MOVING SAID CLIP PUSHER ALONG A PATH EXTENDING OVER, AND BEYOND THE END OF, SAID MANDREL, STOP MEANS FOR STOPPING MOVEMENT OF SAID CLIP PUSHER AT AN INTERMEDIATE STAGE OF ITS FORWARD STROKE AND AFTER SAID CLIP HAS BEEN PUSHED TO THE END OF SAID MANDREL, AND MEANS FOR DISENGAGING SAID STOP MEANS FROM SAID CLIP PUSHER THEREBY TO PERMIT COMPLETION OF THE STROKE OF CLIP PUSHER WHEREBY, THE INITIAL PORTION OF THE STROKE OF SAID CLIP PUSHER CAN BE EFFECTED WHILE SAID TOOL IS HELD IN A CONVENIENT MANNER, AND THE FINAL PORTION OF THE STROKE OF SAID CLIP PUSHER DURING WHICH SAID CLIP IS PUSHED ONTO SAID POST IS CARRIED OUT AS A SEPARATE OPERATION. 